In recent days, people have flooded grocery stores to fill their homes with food, water and emergency supplies. Many stores have entirely cleared out stock, and there's no telling when new shipments will arrive with the storm churning dangerously close.

"No D-batteries to be found," Brian Watanabe tweeted. "I bought an 18-pack of Vienna Sausage because it was the last one lying on the ground and I panicked. Category 5 and it's getting a little Walking Dead-y up here in Hawaii."

"Spam supplies ... nearly gone off the shelves at Wal-Mart," chimed in @tex1sam.

The Category 4 storm is expected to deliver whipping winds, high surf, heavy downpours and flash flooding. Hawaii Gov. David Ige issued an emergency proclamation on Tuesday to speed up the state's response to the storm.

Parts of the Big Island received more than 12 inches of rain in 12 hours overnight.

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As emergency shelters opened, rain began to pour and cellphone alerts went out, the approaching hurricane started to feel real for Hawaii residents.

Media: Fox29

Hurricanes are ranked 1 to 5 according to what is known as the Saffir-Simpson Hurricane Wind Scale. Hurricane Lane is at Category 4, which means winds from 130 to 156 mph.

The Big Island was already starting to see Lane's first effects, Gov. David Ige said at a news conference Wednesday.

The hurricane's outer rain bands were bringing showers to some parts of the island, said Matt Foster, a meteorologist with the National Weather Service.

The eastern side of the island picked up nearly 3 inches of rain in three hours, Foster said.

Meteorologist Chevy Chevalier said Lane may weaken to a Category 3 by Thursday afternoon but that would still be a major hurricane.

"We expect it to gradually weaken as it gets closer to the islands," Chevalier said. "That being said, on our current forecast, as of the afternoon on Thursday, we still have it as a major hurricane."

The central Pacific gets fewer hurricanes than other regions, with about only four or five named storms a year. Hawaii rarely gets hit. The last major storm to hit was Iniki. Others have come close in recent years.

The Federal Emergency Management Agency has several barges with food, water and supplies that it moved into the region ahead of Hurricane Hector, which skirted past the islands more than a week ago, according to FEMA Administrator Brock Long.

The U.S. Navy was moving its ships and submarines out of Hawaii. All vessels not currently undergoing maintenance were being positioned to help respond after the storm, if needed.

President Donald J. Trump issued a disaster declaration Wednesday, authorizing the Department of Homeland Security and the Federal Emergency Management Agency (FEMA), to coordinate disaster relief efforts with the state.